Hi Peter! In Maximo I have that Object Structure. How you can see it's very simply:
Main Object: LOCATIONS
Referenced object: LOCHIERARCHY with the relationship LOCHIERARCHY

Then you must resolve alias conflict (in my case, to all the fields with conflict in the LOCHIERARCHY table, I added the LOC prefix)

Attached I send you the csv used to import locations with their hierarchy and associated with the system.
In the same way you can import it using the "Import" in the "Location" application menu (I use it like this) as with MxLoader.
If it doesn't work to replicate it through MxLoader (you only have to add the header), I will try and send you a working one.
Regards!
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Martin Fabra
ARSAT S.A.
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